Production of organic titanium compounds



Patented Nov. 29, 1949 PRODUCTION OF ORGANIC TITANIUM COMPOUNDS Carl M. Langkammerer, Wilmington, DeL,

or to E. I. du Pont de'Nemo'urs & Com any, Wilmington, Del., a corporation or Dela are No Drawing. Application June 25, 1946 Serial No. 679,267

6 Claims. (Cl. 260 -429) This invention relates to the production of novel, organit: titanium compounds, and more particularlzL to the preparation of new basic titanium salts of lower saturated unsubstituted aliphatic carboxylic acids.

More specifically the invention relates to the production of new basic tetravalent titanium acylates in which the acyl group contains not more than 6 carbon atoms; of new basic tetravalent titanium acylates derived from titanium halides and saturated aliphatic monocarboxylic acids containing not more than 6 carbon atoms; of new basic tetravalent titanium acetates; and to novel methods for preparing such compounds.

In. accordance with this invention, stable basic tetravalent titanium acylates corresponding in composition substantially to the general formula Ti(OH)a:(OCOR)4-1, wherein a: is an integer from 1 to 3 and R is an alkyl radical containing not more than 5 carbon atoms, are prepared by reacting one mol of a tetravalent titanium halide with at least 4 mols of a salt of a saturated aliphatic monocarboxylic acid containing not more than 6 carbon atoms in the presence of an anhydrous organic solvent at a temperature in the range of from 20 C. to 125 C. The resulting basic titanium acylate is highly useful as a modifier for polyhydroxylated polymeric compounds, such as polyvinyl alcohol, partially hydrolyzed ethylene/vinyl acetate polymers, cellulose, starch, and the like. i

In one specific preferred method for preparing my novel compounds, 4 mols of an alkalimetal (sodium, potassium, lithium) acetate, preferably potassium acetate, is dissolved in glacial acetic. acid and-100 parts of acetic acid containing a small amount of water. To the reaction mixture is then added slowly with stirring over a period of /2 hour 94.9 parts of titanium tetrachloride. Six hundred parts of absolute alcohol are added and stirring is continued for minutes, after which the reaction mixture is allowed to standfor 16 hours. The reaction mixture and 144 parts of potassium chloride is separated. The filtrate is vacuum distilled and 300 parts of solvent collected. To the distillation residuethere is added 600 parts of anhydrous ether. The precipitate which 'forms is filtered under anhydrous conditions. Seventy grams of basic titanium acetate, corresponding to the empirical formula Ti(OH)3(OCOCHs) is obtained. Analysis gives the followingvalues: Calcd for CzHsOsTi: C, 15.2%; H, 3.82%; Ti, 30.33%, mol. wt. 157.9. Found: C, 15.59%; H, 3.77%; Ti, 29.47%; molecular weight 474, 457.

The above carbon, hydrogen and titanium values support the empirical formula. but the molecular weight values would indicate that the basic titanium accetate is probably trimeric.

The basic titanium acetate, prepared ,as described above; is initially soluble in ethanol, methanol, and water, butinsoluble in other organic solvents. Alcoholic solutions are relatively f stable while aqueous solutions gel on being about 4 times its weight of absolute ethanol and the reaction mixture-cooled to between 0' C. and 15 C. To the resulting solution is then added, slowly and with continuous stirring, one mol of a stable titanium tetrahalide, preferably the tetrachloride, and the reaction mixture is then allowed Example I To one hundred eighty-six and two tenths parts of potassium acetate is added 600 parts of heated to the boiling point. In the solid form the solubility decreases on standing. After 4 to 6 weeks the product is no longer soluble in solvents in which it was initially soluble. I

Y Example I I One hundred eighty-six and two tenths parts of potassium acetate and 400 parts of absolute alcohol are placed in a reaction vessel and cooled to 10 C. and 94.9 parts of titanium tetrachloride are added over a period of 1.5 hours. The reaction mixture is stirred for an hour and filtered.

The precipitate of potassium chloride which.

' weighs 149 parts is separated by filtration. The

filtrate is evaporated to dryness invacuum.

Fifty-two parts of product is obtained. Analysis gives the following values: Calcd for C4HaO6Ti:

. H, 3.95%; Ti, 27.71%. The analytical values ap- C, 24.0%, H, 4.0%, Ti, 24.0%. Found: C, 22.77%;

proximate those, for Ti(OH)2(OCOCHi)2. The

product is soluble in water, methanol and ethanol and insoluble in. other organic solvents. A 20% aqueous solution is stable at room temperature.

Although potassium acetate has been used in the above examples, it-is to be understood that this is merely preferred and that other metal 3 salts or mixtures of metal salts of lower saturated aliphatic monocarboxylic acids can be generally used. Among examples thereof may be 'mentioned the sodium, potassium, calcium, magnesium, silver, etc., salts of formic acid, acetic acid, propionic acid, butyric acid,valeric acid, etc. As already noted, it is essential in the invention that at least 4 mols of the metal salt be used for each mol of tetravalent titanium halide present in the reaction. Otherwise, the stable, neutral product having the Ti(OH):(OCoR)4-: linkage and requisite properties herein mentioned will not I be obtained.

In place of titanium tetrachloride, there can be used other titanium tetrahalides, e. g., titanium tetrafluoride and titanium tetrabromide. Be-, cause of its availability and reactivity, the preferred titanium tetrahalide for use inthe practice of this invention is the chloride.

Similarly, although acetic acid and absolute ethanol have been used in the examples, it is to ,be understood that methanol, propanol, butanol,

esters, such as ethyl, butyl, and propyl acetates. hydrocarbons, such as benzene, toluene, xylene, gasoline, and the like, can be used equally as well.

The basic tetravalent titanium acylates of this invention can be made, either at ordinary temperatures or at temperatures up to 125 0. Generally, the efiect of the use of elevated temperatures is to accelerate the" rate of reaction.

The basic tetravalent titanium acylates of this invention are useful as modifiers for such polyhydroxylated polymers as polyvinyl alcohols, partially hydrolyzed ethylene/vinyl acetate polymers,

cellulose, starch, and the like. These titanium salts decrease solubility, improve hardness, and

raise the softening point of these polyhydroxylbeing both alcoholand water-soluble.

2. Stable, basic tetravalent titanium acetate,

, corresponding to the formula Ti(OH) 3(OCOCH3) said compound being both alcoholand water-soluble. ,7

' 3. A method for producin a stable, basic tetra- -valent titanium' acylate having the formula Ti(OH)z(OCOR) 4-1, wherein a: is an integer from 1 to 3"and R is an alkyl radical containing not more than 5 carbon atoms, comprising reacting a tetravalent titanium tetrahalide with a metal salt of a saturatedaliphatlc monocarboxylic acid containing not more than 6 carbon atoms, employing in the reaction at least 4 mols of said metal salt for each mol of tetrahalide 5 present, and efiecting said reaction in the presence of substantially anhydrous hydroxyl containing organic solvent.

4. A method for producing a stable, basic tetravalent titanium acylate having the formula 10 Ti(OH)a:(OC0R)4-=, wherein a: is an integer from 1 to 3 and R is an alkyl radical containing not more than 5 carbon atoms, comprising reacting at a temperature ranging from 20-125 C. one mol of a tetravalent titanium halide with at least '4 mols of an alkali metal salt of an unsubstituted,

saturated aliphatic monocarboxylic acid containing not more than 6 carbon atoms in the presence of substantially anhydrous hydroxyl containing organic solvent, and thereafter recovering the resulting acylate product.

5. A method for preparin stable, basic tetravalent titanium acetate corresponding to the formula Ti(OH)3(OCOCH3) comprising reacting at temperatures ranging from 20 C.-125 C. one

mol of titanium tetrachloride with at least 4 mols of an alkali metal acetate in the presence of absolute alcohol, and then isolating and recovering the resulting basic tetravalent titanium acetate.

6. A method for preparin stable, basic tetravalent titanium acetate corresponding to the formula Ti(OH) 3(OCOCH3) comprising dissolving at least 4 mols of potassium acetate in ethanol, cooling the resulting solution to between 0 C. and 15 C., admixing a mol of titanium tetrachloride with said solution, and, on completion of the resulting reaction, isolating and recovering the basic tetravalent titanium acetate produced.

CARL LANGKAMMERER.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,059,740 Liebknecht Apr. 22, 1913 2,027,812 Crundall Jan. 14, 1936 2,233,358 Nutting Feb. 15, 1941 2,316,141 Wainer Apr. 6, 1943 FOREIGN PATENTS Number Country Date 248,251 Germany June 18, 1912 OTHER REFERENCES Fichter et al.: Helvitica Chem. Acta, V, and p. 1082 (1924).

Gina: Zeitschrift fiir Anorg. & Alleg. Chem, vol. 166, pp.306310 (1927).

Rosenheim: Zeit. Anorg. Chem, vol. 26 (1901) page 254. 

